The White House went on the defensive Monday, distancing President Donald Trump from charges filed against two former campaign aides by Special Counsel Robert Mueller in connection with the probe into Russia's attempt to influence last year's presidential election.

The pair, former campaign chairman Paul Manafort and longtime business associate Rick Gates, were named in a 12-count indictment Monday charging money laundering, tax evasion and other violations. They pleaded not guilty Monday in a federal court in Washington.

At Monday's White House briefing, Press Secretary Sarah Huckabee Sanders emphasized that the indictment made no mention of Trump or of any collusion between his presidential campaign and Russia.

Rick Gates, a former campaign official for U.S. President Donald Trump, departs U.S. District Court in Washington, Oct. 30, 2017.

"Today's announcement has nothing to do with the president, has nothing to do with the president's campaign or campaign activity," Sanders said. "We've been saying from day one there's no evidence of Trump-Russia collusion, and nothing in the indictment today changes that at all."

Sanders also said the White House has been given an indication that Mueller's Russia probe would end soon.

The press secretary rejected a reporter's suggestions that the activities of a volunteer Trump foreign policy adviser could be seen as evidence of collusion.

The adviser, George Papadopoulus, pleaded guilty in July to lying to the FBI about his contacts with Russian officials. He could face up to five years in jail.

Sanders on Monday called Papadopoulus a low-level unpaid campaign volunteer whose illegal activities were not campaign-related. "It has nothing to do with the activities of the campaign, it has to do with his failure to tell the truth. That doesn't have anything to do with the campaign or the campaign's activity," she said.

Manafort's attorney Kevin Downing, in a statement after his client's arraignment, noted that the indictment made no mention of Trump, Russia or collusion. "I think you all saw today that President Donald Trump was correct," Downing said. "There is no evidence that Mr. Manafort or the Trump campaign colluded with the Russian government."

Downing argued that his client's activities were legal and aimed at helping a nation struggling to establish democracy after being freed from the Soviet Union.

"Mr. Manafort represented pro-European Union campaigns for the Ukrainian government. And in that, he was seeking to further democracy and to help the Ukraine come closer to the United States and the EU," Downing said. "Those activities ended in 2014, over two years before Mr. Manafort served in the Trump campaign."

'No collusion'

Trump tweeted "There is NO COLLUSION!" shortly after the indictment was unsealed Monday morning.

Another Trump tweet noted that the allegations contained in the indictment against Manafort involve activities that took place before he was briefly head of Trump's campaign last year. The tweet also pointed an accusative finger at Trump's opponent in the election, asking "Why aren't Crooked Hillary and the Dems in the focus?????"

Veteran observers say the indictment's lack of any links to Trump, his campaign or collusion could be seen as an encouraging sign for the president and his administration.

"There is nothing in the indictment that says anything about any kind of collusion, and the truth is this indictment doesn't have anything to do with Russia, it has everything to do with Ukraine," said Bill Mateja, who headed the Justice Department's white-collar crime division under James Comey during the George W. Bush administration.

In comments to VOA, Mateja said he finds it significant that Mueller's indictment targeted only Manafort and Gates.

"A number of people thought there might be additional charges against other people coming right out of the gate," he said. "I think they would have put everything they had evidence for out in the open right here and now. Obviously, they haven't done that."